Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts: Gene/Protein Disease Symptom Drug Enzyme Compound   Target Concepts: Gene/Protein Disease Symptom Drug Enzyme Compound

---

Query: EC:3.1.4.1 (phosphodiesterase)
18,767 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Mouse placental cells are probably constitutive producers of the thromboplastin apoprotein in vitro. The effect of cyclic AMP-elevating compounds on their expression of thromboplastin activity has been studied. Dibutyryl cyclic AMP, the phosphodiesterase inhibitor Ro 20-1724 and the adenyl cyclase stimulator forskolin all decrease the synthesis of thromboplastin. Prostaglandin E2 and the phosphodiesterase inhibitor butyl-methyl-xanthine have a biphasic dose dependent effect. A stimulation was observed at low concentrations, whereas higher doses decreased the synthesis of thromboplastin. Adrenaline had no effect. Combination of two compounds, each at maximally inhibiting concentration gave no significant additive inhibitory effect, showing that they probably act via the same pathway.
...
PMID:Regulation of thromboplastin synthesis in mouse placental cells in vitro. 619 44

EG626 (oxagrelate), a specific inhibitor of cyclic AMP phosphodiesterase, produced in vitro a concentration-dependent inhibition of platelet aggregation induced by collagen and ADP in human platelets. When adenosine was added to the platelet rich plasma (PRP) in the presence of a threshold concentration of EG626, the potency of adenosine in inhibiting platelet aggregation was markedly potentiated. This potentiating effect of EG626 proved to be synergistic, but not additive and was accompanied by a marked accumulation of cyclic AMP in the platelets. The antiaggregating and cyclic AMP increasing activities of adenosine were little affected by S-(p-nitrobenzyl)-6-thioguanosine (6TG), an uptake inhibitor of adenosine, or 2'-deoxycoformycin, an inhibitor of adenosine deaminase. The incorporation of adenosine into platelets was abolished by 6TG. These observations indicate that incorporation of adenosine into platelets is not required for inhibition of aggregation or an increase in cyclic AMP and that the site of action of adenosine is probably extracellular. It also appears that the synergistic action by EG626 is not the result of an inhibition of adenosine uptake and/or adenosine deaminase. This speculation is supported in part by the finding that EG626 also potentiates the antiaggregating activity of 2-chloroadenosine. Antiaggregating activity of prostaglandin E1, an activator of adenylate cyclase, was markedly potentiated in combination with EG626. Dibutyryl cyclic AMP showed a time-dependent inhibition of the platelet aggregation, and the inhibitory action was markedly potentiated by EG626. Qualitatively similar results were obtained with another phosphodiesterase inhibitor, 3-isobutyl-1-methylxanthine (IBMX). All these data suggest that the synergistic potentiation of the antiaggregating activity of adenosine by EG626 might be due to the synergistic accumulation of cyclic AMP in the platelets. This action is mediated through activation of adenylate cyclase by adenosine in combination with the inhibition of cyclic AMP phosphodiesterase by EG626.
...
PMID:Potentiation of antiaggregating activity of adenosine by a phosphodiesterase inhibitor, EG626 (oxagrelate), in human platelets in vitro. 620 94

The effect of cyclic AMP on bone resorption produced by prostaglandin E1 (PGE1) and E2 (PGE2) was studied using 6--7 day-old murine calvarial bones cultured in a chemically defined medium for 48 h. Dibutyryl cyclic AMP inhibited in a dose-related way the prostaglandin-induced mobilization of 45Ca from prelabelled bones. The phosphodiesterase inhibitors, theophylline and 3-isobutyl-methylxanthine, also reduced the release of 45Ca induced by the prostaglandins. It was also found that the doses of the later phosphodiesterase inhibitor needed to inhibit prostaglandin-stimulated mineral mobilization were lower than those needed to reduce unstimulated resorption. The mechanism behind the inhibitory effect of cAMP on prostaglandin-induced bone resorption is unknown, but might be related to the capacity of cAMP to inhibit prostaglandin-stimulated release of lysosomal enzymes, which was also demonstrated in this study.
...
PMID:A revised role for cyclic AMP in prostaglandin-induced bone resorption. 624 86

The effect of cyclic AMP and related compounds on both in vivo and in vitro epidermal cell migration during wound closure in the adult newt was examined. Cyclic AMP (cAMP) and N6,O2'-dibutyryl cyclic AMP (db-cAMP) inhibited migration both in vivo and in vitro when used with equimolar concentrations of theophylline, an inhibitor of 3',5'-cyclic nucleotide phosphodiesterase. Neither db-cAMP nor theophylline alone inhibited migration in vivo. Adenosine 5' monophosphate (AMP), cyclic guanosine 3',5' monophosphate (cGMP) and imidazole, a potentiator of phosphodiesterase were tested in vivo and had no effect on migration. Isoproterenol and epinephrine, which are known to stimulate adenylate cyclase, inhibited migration in vitro. Experiments using the protein synthesis inhibitor, cycloheximide, suggest that cAMP could be acting partially through regulation of protein synthesis but that other factors are involved. Dibutyryl cyclic AMP and theophylline had no effect on the incorporation of 3H-leucine into protein. The inhibition of migration both in vivo and in vitro provides further evidence for a role of cAMP in the regulation of cell motility.
...
PMID:Effect of cAMP and related compounds on newt epidermal cell migration both in vivo and in vitro. 625 Nov 54

Intratesticular injection of prostaglandin E2 (PGE2) and F2 alpha (PGF2 alpha) caused stimulation of ornithine decarboxylase (ODC) activity in the testis of immature rats. PGE2 at a dose of 10 microgram per testis was maximally effective 2 hours after the injection. Dibutyryl cyclic AMP (cAMP) and 1 methyl, 3-isobutyl xanthine (MIX), a phosphodiesterase inhibitor, also stimulated ODC activity. Simultaneous injection of PGE2 and FSH or LH caused additional stimulation of ODC activity. Similarly injection of PGE2 in addition to cAMP or MIX also caused increased stimulation of ODC. Indomethacin (IM, 60 microgram/testis) inhibited LH, FSH or cAMP induced ODC activity. However, IM at the same dose inhibited the synthesis of total proteins. These results suggest that PGE2 and PGF2 alpha stimulate the activity of ODC. The action of prostaglandins may be independent of the action of gonadotropic hormones. cAMP appears to mediate the action of prostaglandins in the testis of rat.
...
PMID:Effect of prostaglandins on ornithine decarboxylase activity in the testis of immature rat. 625 76

Thyroid hormones are known to enhance normal erythroid colony growth (CFUE) and this enhancement depends on a functional beta 2-adrenergic receptor mechanism. we investigated the response of Friend cells to thyroid hormones, catecholamines, and other compounds influencing cellular cAMP activity. The thyroid hormones L-T3, L-T4, and "reverse T3" stimulated erythroleukemia colony growth in a serum-substituted methylcellulose culture system with peak activity at 10(-7) M. Various beta-adrenergic compounds enhanced Friend leukemia colony growth; however, the alpha-adrenergic agonist phenylephrine was inactive. Dibutyryl cyclic AMP and the phosphodiesterase inhibitor theophylline also enhanced Friend leukemia colony formation. Adrenergic antagonists with beta 2 specificity abrogated the stimulatory effect of L-T3, L-T4, and of "reverse T3" at equimolar concentrations. These experiments demonstrate that thyroid hormones, beta-adrenergic agonists, the phosphodiesterase inhibitor theophylline, and dbcAMP have a direct effect on the proliferation of Friend erythroleukemia cells. We conclude that thyroid hormones' action requires a functioning beta 2-adrenergic receptor mechanism. Thyroid hormones directly modulate the growth of neoplastic erythroid cells in a manner consistent with their effects on normal erythropoiesis.
...
PMID:Beta 2 receptor-mediated stimulation of Friend erythroleukemia cell growth by thyroid hormones. 627 12

1. The effects of isoprenaline (10(-6) M) on relaxation, unidirectional as well as net Ca(2+) fluxes, and cyclic AMP levels were investigated in rabbit aorta under the condition of high-K(+) depolarization in the presence of phentolamine (10(-5) M).2. Isoprenaline (10(-6) M) caused significant inhibition of Ca(2+) influx stimulated by 145 mM-K(+) (0 Na(+)) solution. The time courses of Ca(2+) influx inhibition and relaxation by isoprenaline were parallel. Isoprenaline also caused a significant inhibition of high-K(+)-induced gain in net Ca(2+) content.3. Ro 20-1724 (1 mM), a phosphodiesterase inhibitor, also caused relaxation and Ca(2+) influx inhibition in high-K(+)-depolarized rabbit aorta. Pre-treatment with Ro 20-1724 potentiated isoprenaline-induced Ca(2+) influx inhibition and relaxation.4. Isoprenaline and Ro 20-1724 each alone increased cyclic AMP levels. Furthermore pre-treatment with Ro 20-1724 caused potentiation of isoprenaline-induced increases in cyclic AMP levels.5. At submaximal concentration, D600 (10(-7) M) caused partial inhibition of high-K(+)-stimulated Ca(2+) influx and produced relaxation. However, unlike Ro 20-1724, it did not potentiate isoprenaline-induced Ca(2+) influx inhibition and relaxation. D600 does not increase cyclic AMP levels in smooth muscle.6. Dibutyryl cyclic AMP (1 mM), a lipid-soluble analogue of cyclic AMP, caused relaxation and inhibited high-K(+)-stimulated Ca(2+) influx.7. Isoprenaline failed to cause stimulation of Ca(2+) efflux in high-K(+)-depolarized rabbit aorta.8. It is concluded that the inhibition of Ca(2+) influx may be one of the mechanisms by which beta-receptor stimulation can reduce intracellular free Ca(2+) to promote relaxation of smooth muscle. The data support the involvement of cyclic AMP in this action of the beta-agonist.9. Since the experiments were conducted in 145 mM-K(+) (0 Na(+)) depolarizing conditions, the role of hyperpolarization or of a Na(+)-Ca(2+) exchange mechanism in isoprenaline-induced Ca(2+) influx inhibition and/or relaxation can be excluded.
...
PMID:Effects of beta-adrenergic stimulation on calcium movements in rabbit aortic smooth muscle: relationship with cyclic AMP. 629 69

1. Interleukin-1 beta (IL-1 beta) is a potent stimulant of inducible nitric oxide synthase (iNOS) mRNA and nitric oxide (NO) production in vascular smooth muscle (VSM) cells in culture. These studies investigate the role of adenosine 3':5'-cyclic monophosphate (cyclic AMP) in this process. 2. Dibutyryl cyclic AMP (db cyclic AMP, 0.1-1 mM), forskolin (1-10 microM) and the phosphodiesterase inhibitor, Ro 20-1724 (1-10 microM), all of which increase intracellular cyclic AMP, had no effect on NO production when added alone but markedly enhanced NO production by IL-1 beta-stimulated VSM cells in a dose-dependent manner. Consistent with a cyclic AMP-mediated action, isoprenaline (1-10 microM) increased NO production from IL-1 beta-stimulated cells. Dibutyryl cyclic GMP (db cyclic GMP) had no effect at concentrations up to 1 mM. 3. Pursuing these observations, iNOS protein levels were examined by Western blot analysis and iNOS mRNA levels were measured by reverse transcription and amplification of the resultant cDNA using the polymerase chain reaction. In addition to enhancing NO production, db cyclic AMP increased iNOS protein and mRNA above that produced by IL-1 beta alone. 4. These data demonstrate a major effect of cyclic AMP on cytokine-induced NOS activity in VSM cells, mediated at least in part by regulating synthesis of iNOS, and has implications for the pathogenesis and management of septic shock.
...
PMID:Induction of nitric oxide synthase in cultured vascular smooth muscle cells: the role of cyclic AMP. 752 Dec 56

Cardiotonic agents that belong to a group of phosphodiesterase inhibitors--vesnarinone, amrinone, enoximone, pimobendan, MS-857 and E-1020--inhibited the 35 mM KCl- and 10(-7) M norepinephrine-induced contractions of helical strips from rat thoracic aorta in a concentration-dependent manner. In the absence of extracellular Ca2+, 10(-7) M phorbol 12,13-dibutyrate caused a sustained contraction of the muscle strip without an increase in intracellular Ca2+ level ([Ca2+]i). The phorbol 12,13-dibutyrate-induced contractions in Ca2+(-)free buffer were also inhibited by the cardiotonic phosphodiesterase inhibitors. A cyclic GMP-inhibited cyclic nucleotide phosphodiesterase was partially purified from rat aorta and the activity of the phosphodiesterase was inhibited by the cardiotonic agents. The inhibitory effect of these agents on the KCl-, norepinephrine-and phorbol 12,13-dibutyrate-induced contractions showed good correlations to the concentrations of the agents producing 50% inhibition (IC50) of cyclic GMP-inhibited cyclic nucleotide phosphodiesterase. Vesnarinone inhibited the norepinephrine-induced contraction with a decrease in [Ca2+]i, but inhibited the phorbol 12,13-dibutyrate-induced contraction in Ca(2+)-free buffer without significant changes in [Ca2+]i. Dibutyryl cyclic AMP and NKH477 also inhibited the phorbol 12,13-dibutyrate-induced contraction in Ca(2+)-free buffer without significant changes in [Ca2+]i. The six cardiotonic phosphodiesterase inhibitors increased the cyclic AMP contents of the muscle strips. These results suggest that the inhibitory actions of these cardiotonic phosphodiesterase inhibitors on cyclic GMP-inhibited cyclic nucleotide phosphodiesterase may cause vasorelaxation through a decrease in [Ca2+]i and an inhibitory effect on a Ca(2+)-independent contractile process (or a decrease in Ca(2+)-sensitivity of contractile elements).
...
PMID:Ca2+(-)dependent and Ca2+(-)independent vasorelaxation induced by cardiotonic phosphodiesterase inhibitors. 840 22

The effect of T-440, a selective type IV phosphodiesterase (PDE IV) inhibitor on interleukin (IL)-5 production by peripheral blood mononuclear cells (PBMCs) of atopic asthmatic subjects was investigated. PBMCs produced IL 5 following challenge with specific allergen in vitro. T-440 suppressed allergen-induced IL-5 production significantly at a concentration of 1 microgram/ml. T-440 inhibited cyclic AMP-phosphodiesterase (PDE) activity in a concentration dependent manner and raised the intracellular cyclic AMP level of PBMCs significantly. Dibutyryl cyclic AMP suppressed IL-5 production by PBMCs in a similar way to T-440, suggesting that the increase of intracellular cyclic AMP caused by T-440 reduces IL-5 production. T-440 may be an effective agent to treat atopic diseases associated with eosinophilic inflammation, e.g. asthma and atopic dermatitis.
...
PMID:A novel phosphodiesterase inhibitor, T-440: possible management of eosinophilic inflammation by down-regulation of interleukin-5 production. 890 5


<< Previous 1 2 3 4

---